Roll forming sized channel

ABSTRACT

Flat strip stock is formed in a progressive rolling setup by a series of sets of dies to a channel form in which the sides of the channels are of arcuate inwardly concave configuration terminating in parallel inwardly spaced flat flanges. The stock is completely shaped by a series of dies to the required configuration but of slightly undersize internal dimensions. The stock is then drawn over a mandrel shaped and dimensioned to produce a slight expansion of the channel form to produce inside dimensions suitable for cooperation with a supporting track on which the channel form is slidable.

United States Patent [191 Pickles et al.

[ Oct. 28, 1975 ROLL FORMING SIZED CHANNEL [73] Assignee: 'Ferro Manufacturing Corporation,

Detroit, Mich.

22 Filed: Sept. 11, 1974 211 Appl. No.: 505,035

Saito et al 72/176 3,707,088 12/1972 King et al. 72/181 Primary ExaminerMilton S. Mehr Attorney, Agent, or F irmWhittemore, l-lulbert &

Belknap [5 7] ABSTRACT Flat strip stock is formed in a progressive rolling setup by a series of sets of dies to a channel form in which the sides of the channels are of arcuate inwardly concave configuration terminating in parallel inwardly spaced flat flanges. The stock is completely shaped by a series of dies to the required configuration but of slightly undersize internal dimensions. The stock is then drawn over a mandrel shaped and dimensioned to produce a slight expansion of the channel form to produce inside dimensions suitable for cooperation with a supporting track on which the channel form is slidable.

2 Claims, 12 Drawing Figures U.S. Patent Oct.28, 1975 She et1of2 3,914,970

FIG. 5

US. Patent 0a. 28, 1975 Sheet 2 of2 3,914,970

FIGS

FIG.7

FIG. I2

FIG. I I 79 FIG. 10

ROLL FORMING SIZED CHANNEL BRIEF SUMMARY OF THE INVENTION The present invention relates to the production by progressive rolling of flat strip stock into a channel form of specific configuration. The channel form is useful to produce carriages slidable on elongated track structure and more particularly, to provide channel form slides cooperable with the track structure.

More specifically, the carriage slides are of channel configuration having a flat base, arcuate sides of. 180 extent, and inwardly extending confronting flat flanges parallel to the flat base. These carriage slides are adapted to slide upon supporting track structure providing outwardly extending flat parallel flanges received within the arcuate sides of the carriage slide, the outwardly extending flanges of the track being provided with low friction bearing material, preferably a low friction plastic material.

From the foregoing description it will be apparent that the operation of the carriage slide is dependent solely on the internal dimensions of the carriage slide and that its external dimensions are not of controlling signficance. On the other hand, the method of producing the carriage slides necessarily involves rolling the exterior surfaces thereof to desired dimensions, without reference to internal dimensions.

In accordance with the present invention the carriage slides are rolled to substantially the final desired shape and are so produced as to provide slightly undersized internal dimensions. The critical internal dimensions are a radii of the sides and the transverse spacing thereof.

In accordance with the present invention the completely rolled channel-shaped strip material is drawn by a pair of puller rolls over an accurately shaped mandrel to produce internal dimensions in the channel of precisely the required amount.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary perspective view, partly in section, showing the channel-shaped carriage slide and associated structure.

FIG. 2 is a diagrammatic view illustrating the progressive roll formation of strip material to the required channel form, together with drawing of the strip material over the expanding mandrel.

FIG. 3 is an enlarged fragmentary sectional view through the final rolling station, on the line 33, FIG. 2

FIG. 4 is an enlarged fragmentary transverse sectional view showing puller rolls on the line 4-4, FIG. 2.

FIG. 5 is an enlarged transverse view, partly in section, on the line 55, FIG. 2.

FIG. 6 is a fragmentary view, partly in section, on the line 6-6, FIG. 5.

FIG. 7 is an elevational view of the mandrel.

FIG. 8 is a side view of the mandrel seen in FIG. 7.

FIG. 9 is a plan view of the mandrel seen in FIG. 7.

FIG. 10 is an elevational view of the mandrel holder.

FIG. 11 is a side elevational view of the mandrel holder.

FIG. 12 is a plan view of the mandrel holder.

DETAILED DESCRIPTION The present invention relates to a carriage slide particularly useful as the means for slidably mounting a seat, particularly a vehicle seat, for longitudinal sliding adjustment on track structure. The track structure may include means for effecting vertical and tilting adjustment of the track and provides for adjustment of the vehicle seat longitudinally of the track in whatever position of adjustment the track is fixed.

Referring now to FIG. 1, the track is illustrated at 10 and comprises a channel having a bottom wall 12, flat side walls 14, and outwardly extending flanges 16, the flanges being flat and occupying the same plane.

The carriage slide is indicated generally at 20 and comprises a channel having a flat central web 22, arcuate sides 24, and inwardly extending flat flanges 26 which extend towards each other in the same plane.

The web 20, arcuate side walls 24, and flanges 26 define inwardly concave channels or grooves designated 28. The oppositely directed flat flanges 16 of the track 10 are provided with low friction bearing means indicated at 30 which preferably are formed of low friction plastic material.

With this arrangement the carriage slides 20 are freely slidable longitudinally of the track 10, yet are adequately supported against transverse movement and are adapted to run silently on the low friction bearing material which conforms to the inner surfaces of the confronting grooves 28.

It will of course be apparent from an inspection of FIG. 1 that the critical dimensions of the carriage slide 20 are its internal dimensions, particularly, the radius of curvature of the semi-cylindrical sides 24 and the spacing between these semi-cylindrical side portions. Also critical of course, is the spacing between the flanges 26 and the web 22.

Carriage slides 20 are produced, according to the present invention, from flat strip material which is rolled by a succession of sets of rolls from the flat form to the specific final form best illustrated in FIG. 1.

In FIG. 2 there is diagrammatically illustrated a plurality of stations, of which stations designated 32, 34 and 36 are final rolling stations, and the station 38 is a station at which are provided a pair of puller rolls adapted to pull the generally completed channel formed strip material over a final shaping mandrel 40 which is effective to produce precisely the required shape and dimensions at the interior of the carriage slide 20, without reference to any dimensions at its exterior.

It will be observed from the foregoing that while the strip is formed into the required channel form by sets of rolls, all of these operate on the exterior of the channel shape as it is caused progressively to approach its final desired shape. Thus, the channel as it is essentially completed at station 41, has assumed a shape dependent upon engagement with the succession of sets of rolls with its exterior surface, without reference to any shaping or dimensions at its interior surface. The functioning of the carriage slide 20 is solely dependent on its internal shaping and dimensions. Accordingly, the generally completed channel formed carriage slide is finish-roll formed to a condition in which its internal dimensions are slightly smaller than desired. These dimensions are enlarged by drawing the channel strip over a mandrel the shaping and dimensions of which are such that after the strip passes beyond the mandrel its internal dimensions are precisely those required.

Referring now to FIG. 3 there is shown a fragmentary enlargement of the structure at station 36 where rollers 42 and 44 cooperate with the channel section at this station, here designated 46. It will be observed that the lower roller 42 has a peripheral groove 48 having a bottom wall which is flat in section, and side walls which in section are arcuate and have an angularity extent of 90. The upper roller 44 has a groove 50 including a peripheral radially extending rib 52 adapted to engage the inner flat surface of the strip and to extend beyond the inwardly extending flanges of the strip at this station. This represents the final forming station and the carriage slide as completed at this station has accurately controlled external configuration and dimensions, but no assurance that the critical internal dimensions are as required. In order to assure accuracy in the critical internal dimensions, the internal dimensions of the strip as completed at the station 36 are slightly undersize.

Referring now to FIG. 4 there is illustrated a pair of puller rolls comprising an upper roll 54 dimensioned to extend between the intumed flanges of the strip which are here designated 56, and to engage the inner surface of the flat web 22 of the channel as illustrated. A second puller roll 58 is provided and the web 22 of the channel at this station is engaged between rolls 54 and 58 which are driven to pull the channel over the mandrel at station 41.

Referring now to FIG. there is illustrated a sectional view through the mandrel 40 which is mounted in the recess of a mandrel holder 62 as will subsequently appear. The mandrel 40 includes laterally extending tapered ears 64 which are accurately dimensioned to expand the interior of the strip forming the carriage slide so that upon leaving the mandrel 60 it assumes the final required dimension.

Referring now to FIGS. 7, 8 and 9, the details of the sizing mandrel 60 are shown. The mandrel includes the laterally extending ears 64 having tapered end portions as indicated at 66 and 68, and central portions 70 having semi-cylindrical surface portions 72 and flat upper and lower surface portions 74 and 75. It will be observed that the bottom surface 76 of the block 77 is spaced slightly above the flat undersurfaces of the central portions 70 of the ears 64, so that only the ears 64 of the sizing mandrel engage the interior surface of the channel and particularly, the interior surfaces of the grooves thereof.

The tapered portions 66 and 68 lead into the interior of the inwardly confronting channels in the formed strip and as the strip is drawn over the sizing mandrel, the internal dimensions of the strip are brought to final required dimension by the ears 64 of the mandrel.

The mandrel includes the upstanding block portion 77 having an interior tapped opening 78 for a purpose which will presently appear.

Referring now to FIGS. 10, 11 and 12, the mandrel holder 62 is illustrated as comprising a generally rectangular elongated block 79 having a rectangular recess 80 formed at its underside and dimensioned to receive the upwardly extending block portion 77 of the sizing mandrel, substantially as seen in FIGS. 5 and 6. The mandrel holder is provided with a drilled hole 81 for receiving an assembly screw which extends into the tapped opening 78 of the sizing mandrel.

The assembly of the sizing mandrel and holder, as best illustrated in FIG. 5, provides a construction in which the ears 64 of the sizing mandrel are adapted to be positioned within the confronting grooves at opposite sides of the formed strip as it passes over the mandrel.

The mandrel holder 44 is provided with tapped openings 82 for attachment to suitable supporting structure (not shown).

It will of course be apparent that in providing the shaping ears 64 on the sizing mandrel, attention must be given to any spring-back or recovery of the carriage slide structure after it has passed the mandrel. No further change in shape or dimension occurs, since the completed strip is drawn by the puller rolls 54, 58 which engage only the flat web portion 22 of the carriage slide 20.

What we claim as our invention is:

1. The method of forming flat strip material to channel shape and finishing to exact internal dimensions, which comprises advancing initially flat strip material through a series of sets of forming rolls to progressively shape the material to a channel configuration having in transverse section a flat web, semi-cylindrical side walls and flat coplanar flanges having free edge portions extending toward each other, said web, side walls and flanges defining a channel shape the sides of which provide opposed concave confronting lateral grooves having semi-cylindrical bottom portions and adjacent flat parallel wall surfaces for the reception of correspondingly shaped bearing material constituting supporting track structure, roll forming the strip to the required shape but with slightly undersized internal dimensions in a final series of sets of rolls shaped to engage only exterior surfaces of said channel, and expanding the channel to the required final internal dimensions by drawing the finish-rolled strip over a sizing mandrel spaced longitudinally in the direction of advance from the final set of forming rolls and arranged to contact only interior surfaces of said confronting grooves to expand the confronting grooves to provide internal dimensions thereof independent of any external dimensions thereof.

2. The method as defined in claim 1 which comprises drawing the finish-rolled channel over the sizing mandrel by engagement of a first pull roll extending between the edges of the spaced flanges and engaging the flat inner surface of the flat web, and a second pull roll opposed to the first pull roll and engaging the flat outer surface of the flat web, the pull rolls being spaced longitudinally in the direction of advance from sizing mandrel. 

1. The method of forming flat strip material to channel shape and finishing to exact internal dimensions, which comprises advancing initially flat strip material through a series of sets of forming rolls to progressively shape the material to a channel configuration having in transverse section a flat web, semicylindrical side walls and flat coplanar flanges having free edge portions extending toward each other, said web, side walls and flanges defining a channel shape the sides of which provide opposed concave confronting lateral grooves having semicylindrical bottom portions and adjacent flat parallel wall surfaces for the reception of correspondingly shaped bearing material constituting supporting track structure, roll forming the strip to the required shape but with slightly undersized internal dimensions in a final series of sets of rolls shaped to engage only exterior surfaces of said channel, and expanding the channel to the required final internal dimensions by drawing the finish-rolled strip over a sizing mandrel spaced longitudinally in the direction of advance from the final set of forming rolls and arranged to contact only interior surfaces of said confronting grooves to expand the confronting grooves to provide internal dimensions thereof independent of any external dimensions thereof.
 2. The method as defined in claim 1 which comprises drawing the finish-rolled channel over the sizing mandrel by engagement of a first pull roll extending between the edges of the spaced flanges and engaging the flat inner surface of the flat web, and a second pull roll opposed to the first pull roll and engaging the flat outer surface of the flat web, the pull rolls being spaced longitudinally in the direction of advance from sizing mandrel. 